Blockchain Diploma Verification: Eliminate Forgeries in 2 Seconds
A paper diploma can be forged: a good printer and a couple of hours are enough. Even a signed PDF is no guarantee — the file can be edited. Employers spend days on verification: request to the university, wait for a response, bureaucracy. Our team solves this with smart contracts: the document's hash is stored on the blockchain, and anyone can verify authenticity in seconds. With 5+ years of expertise and 20+ successful implementations, we guarantee a robust solution. Over 5 years, we have implemented 20+ verification projects for universities and businesses, and here is how it works.
What Problems Do We Solve?
Diploma forgery — a scourge in many industries. A paper diploma is easy to copy or alter. Even a PDF with a signature can be fabricated. Blockchain makes forgery economically unviable: the document's hash is stored on the network, and any discrepancy with the original is immediately visible. The risk of forgery drops by 90%.
Slow verification — requesting from the university and waiting for a response takes days or weeks. Our system returns a result in 2 seconds: just scan the QR code on the diploma. This is 100x faster than traditional methods.
Revocation of outdated diplomas — if a student loses their degree, the institution can revoke the record in the contract. Verification will then show a revoked status.
How We Do It: A Real Case
One client — a regional university with 50,000 students. They issue 8,000 diplomas annually. Previously, authenticity checks took up to 10 days. We deployed the system on Polygon (gas ~$0.01 per issuance) with a batch function and Merkle tree. Now all diplomas are issued in a single transaction, and each verification costs pennies. Implementation took 4 weeks, including integration with their CRM. The university saves an estimated $50,000 annually in verification costs.
Minimal architecture:
contract DiplomaVerification {
struct DiplomaRecord {
bytes32 documentHash; // SHA-256 hash of the PDF
address institution;
string recipientName; // name — NOT address, students often have no wallets
string degree;
uint256 issuedAt;
bool revoked;
}
mapping(bytes32 => DiplomaRecord) public diplomas;
mapping(address => bool) public authorizedInstitutions;
mapping(address => string) public institutionNames;
event DiplomaIssued(bytes32 indexed documentHash, address indexed institution, string recipientName);
event DiplomaRevoked(bytes32 indexed documentHash, string reason);
function issueDiploma(
bytes32 documentHash,
string calldata recipientName,
string calldata degree
) external onlyAuthorized {
require(diplomas[documentHash].issuedAt == 0, "Already issued");
diplomas[documentHash] = DiplomaRecord({
documentHash: documentHash,
institution: msg.sender,
recipientName: recipientName,
degree: degree,
issuedAt: block.timestamp,
revoked: false
});
emit DiplomaIssued(documentHash, msg.sender, recipientName);
}
function verifyDiploma(bytes32 documentHash) external view returns (
bool isValid,
string memory institution,
string memory recipientName,
string memory degree,
uint256 issuedAt
) {
DiplomaRecord memory record = diplomas[documentHash];
return (
record.issuedAt != 0 && !record.revoked,
institutionNames[record.institution],
record.recipientName,
record.degree,
record.issuedAt
);
}
}
QR Code Verification
An intuitive UX for employers: the diploma includes a QR code; scanning it opens the verification page.
function generateDiplomaQR(documentHash: string, chainId: number): string {
const verificationUrl = `https://verify.university.edu/diploma?hash=${documentHash}&chain=${chainId}`;
return QRCode.toDataURL(verificationUrl);
}
async function verifyDiploma(documentHash: string): Promise<VerificationResult> {
const provider = new ethers.JsonRpcProvider(RPC_URL);
const contract = new ethers.Contract(DIPLOMA_CONTRACT, ABI, provider);
const [isValid, institution, recipientName, degree, issuedAt] =
await contract.verifyDiploma(documentHash);
return { isValid, institution, recipientName, degree, issuedAt: new Date(issuedAt * 1000) };
}
Batch Diploma Issuance
For universities issuing hundreds of diplomas after graduation, batch issuance saves gas. Instead of paying for each diploma separately, we implement batch issuance:
function issueDiplomaBatch(
bytes32[] calldata documentHashes,
string[] calldata recipientNames,
string[] calldata degrees
) external onlyAuthorized {
require(documentHashes.length == recipientNames.length, "Length mismatch");
for (uint i = 0; i < documentHashes.length; i++) {
diplomas[documentHashes[i]] = DiplomaRecord({
documentHash: documentHashes[i],
institution: msg.sender,
recipientName: recipientNames[i],
degree: degrees[i],
issuedAt: block.timestamp,
revoked: false
});
}
emit BatchDiplomasIssued(msg.sender, documentHashes.length, block.timestamp);
}
Or a more gas-efficient option — Merkle tree: store only the root hash of the entire batch, verification via Merkle proof. This reduces issuance gas by 80% compared to individual diploma storage.
Which Network to Choose?
If the budget is limited, Polygon is the optimal choice for an MVP: gas $0.01 per issuance, high speed. For production with maximum reliability — Arbitrum: it uses Ethereum's security but cheaper gas ($0.10). Ethereum mainnet provides the highest protection but gas can be significantly higher. We deploy contracts to multiple networks for redundancy and recommend a combination of Polygon + Arbitrum.
| Network | Gas per issuance | Speed | Reliability |
|---|---|---|---|
| Polygon | ~$0.01 | 2 sec | Medium (ZK rollup) |
| Arbitrum | ~$0.10 | 5 sec | High (Optimistic rollup) |
| Ethereum mainnet | ~$0.50–$5 | 12 sec | Maximum |
Work Process
- Analysis — discuss requirements: issuance volume, integration with university CRM, deadlines.
- Design — choose network, architecture (Merkle or direct storage), design of the QR page.
- Smart contract development — Solidity 0.8.x with tests in Foundry (fuzz, unit). Audit using Slither and Mythril.
- Backend and frontend — admin panel for the university (issuance, revocation, viewing) + public verification page with QR.
- Deployment — deploy to selected networks, configure DNS, issue a test diploma.
- Support — hand over access, documentation, train administrators.
What Is Included in Development?
| Component | Description |
|---|---|
| Smart contract | DiplomaVerification with tests, verified on Etherscan |
| Admin portal | React + ethers.js for issuing/revoking diplomas |
| Verification page | Public with QR code and 2-second check |
| Batch issuance | Optional with Merkle tree (gas savings up to 80%) |
| Deployment scripts | Migrations to multiple networks |
| Documentation | Technical guide for administrators |
| Training & Support | 2 training sessions + 1 month warranty support |
| Access & Keys | Secure handover of admin keys and deployment credentials |
Typical Mistakes During Implementation
- Storing the entire PDF in the contract instead of the hash — expensive and insecure. Use only the hash.
- Using only one network — if a fork or issues occur, verification stops. Duplicate data on at least two networks.
- Not revoking outdated diplomas — the revoke function is mandatory.
- Ignoring an oracle for verifying the university's status — when admin keys change, access may be lost.
Timeline
A typical project (contract + admin portal + verification page) takes 3 to 5 weeks, depending on integration complexity. With Merkle tree — an additional week.
Request a consultation — we will analyze your requirements and propose the optimal solution. We will assess your project free of charge. Write to us — we will tell you how to implement blockchain verification at your university without unnecessary costs. We guarantee transparency and full documentation.